Surgical stapling instrument

ABSTRACT

A surgical stapling instrument includes an anvil body defining a longitudinal axis, a cartridge body coupled to the anvil body, a staple cartridge releasably mounted relative to the cartridge body, a firing member mounted to the cartridge body and configured for longitudinal movement through the staple cartridge, and a lockout member supported by the cartridge body. The lockout member defines a single longitudinal slot for at least partial reception of the firing member. The lockout member is configured for movement from a locked position preventing longitudinal movement of the firing member to a release position permitting longitudinal movement of the firing member upon mounting of the staple cartridge to the cartridge body.

BACKGROUND 1. Technical Description

The present disclosure relates to a surgical stapling instrument, and, more particularly, relates to a lockout for a linear stapling instrument, which prevents firing of the stapling instrument until proper installation of a staple cartridge. The present disclosure further relates to a low profile firing member for use with the lockout, and having sufficient compressive strength to deliver multiple rows of staples without risk of deformation or malfunction of the firing member.

2. Background of Related Art

Surgical stapling instruments for dispensing staples to join tissue during surgical procedures are well known. Linear type surgical stapling instruments typically include a staple cartridge housing a plurality of staples and an anvil disposed in opposition to the staple cartridge. Tissue is disposed between the staple cartridge and the anvil, and these components are approximated. A firing mechanism including a double channel or U-shaped drive is activated to sequentially eject staples from the staple cartridge through the tissue for deformation by the anvil. A knife may be utilized to sever tissue between sets of the applied staples. Several stapling instruments incorporate one or more mechanisms to prevent firing of the instrument until the staple cartridge and the anvil are approximated.

SUMMARY

The present disclosure is directed to further improvements in surgical stapling instruments such as, e.g., a linear stapling instrument. In accordance with one exemplary embodiment, a surgical stapling instrument includes an anvil body defining a longitudinal axis, a cartridge body coupled to the anvil body, a staple cartridge releasably mounted relative to the cartridge body, a firing member mounted to the cartridge body and configured for longitudinal movement through the staple cartridge, and a lockout member supported by the cartridge body. The lockout member defines a single longitudinal slot for at least partial reception of the firing member. The lockout member is configured for movement from a locked position preventing longitudinal movement of the firing member to a release position permitting longitudinal movement of the firing member upon mounting of the staple cartridge to the cartridge body.

In embodiments, the lockout member includes a lockout shelf and the firing member includes a lockout recess. The lockout shelf is configured to engage the lockout recess when in the locked position of the lockout member, and is configured to release the lockout recess when in the release position of the lockout member. In some embodiments, the lockout member is pivotally mounted to the cartridge body, and is configured for pivotal movement between the locked position and the release position. In certain embodiments, the lockout member is normally biased toward the locked position. In embodiments, a spring, e.g., a torsion spring, is coupled to the lockout member and is operatively engageable with the cartridge body. The spring is configured to normally bias the lockout member toward the locked position.

In some embodiments, the lockout member includes at least one release leg configured to be engaged by the staple cartridge upon mounting of the staple cartridge to the cartridge body to facilitate movement of the lockout member from the locked position to the release position. In certain embodiments, the at least one release leg includes an arcuate raised segment.

In embodiments, the firing member is configured for longitudinal movement between an initial proximal position and an actuated distal position. In some embodiments, the lockout member includes a stop proximal of the lockout shelf. The stop is configured to engage the lockout recess of the firing member to prevent proximal movement of the firing member beyond the initial proximal position.

In certain embodiments, the firing member is configured to traverse the single longitudinal slot of the lockout member during movement of the firing member between the initial proximal position and the actuated distal position. In embodiments, the firing member includes a lower arcuate segment and a plate segment. In some embodiments, the single slot of the lockout member includes a first slot portion configured for accommodating the arcuate segment of the lockout member and a second slot portion configured for accommodating the plate segment of the firing member. In certain embodiments, the first slot portion defines a first dimension orthogonal to the longitudinal axis and the second slot portion defines a second dimension orthogonal to the longitudinal axis whereby the first dimension is greater than the second dimension.

The lockout member of the present disclosure ensures that the stapling instrument cannot be fired until the staple cartridge is properly installed within the instrument. This enhances usability of the instrument and prevents improper firing of surgical staples. The firing member incorporates structural features including, e.g., the lower arcuate segment, which increase the compressive strength of the firing member to enable firing of multiple rows of staples while reducing the overall profile of the firing member. The reduced profile may provide additional space for the other operating components of the stapling instrument.

Other features of the present disclosure will become more readily apparent from the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments of the presently disclosed surgical stapling instrument are described herein below with reference to the drawings, wherein:

FIG. 1 is a perspective view of an exemplary embodiment of a surgical stapling instrument incorporating the lockout member and the firing member of the present disclosure;

FIG. 2 is an exploded perspective view of the surgical stapling instrument illustrating the cartridge body, the anvil body, the staple cartridge, the firing member and the lockout member;

FIG. 3 is an enlarged view of the area of detail identified in FIG. 2 illustrating the lockout member;

FIGS. 4-5 are first and second perspective views of the lockout member;

FIG. 6 is a rear axial view illustrating the lockout member and the firing member extending through the lockout member;

FIG. 7 is a perspective view of the cartridge body and the staple cartridge prior to mounting of the staple cartridge to the cartridge body and with the firing member in an initial proximal position;

FIG. 8 is an enlarged view of the area of detail identified in FIG. 7 illustrating the lockout member in the locked position engaging the firing member;

FIG. 9 is a cross-sectional view taken along the lines 9-9 of FIG. 7;

FIG. 10 is a cross-sectional view taken along the lines 10-10 of FIG. 7;

FIG. 11 is a perspective view of the cartridge body with the staple cartridge mounted to the cartridge body;

FIG. 12 is a perspective view in partial cross-sectional taken along the lines 12-12 of FIG. 11 illustrating the lockout member in the release position;

FIG. 13 is a cross-sectional view taken along the lines 13-13 of FIG. 11; and

FIG. 14 is a perspective view illustrating the firing member in the actuated distal position.

DETAILED DESCRIPTION OF EMBODIMENTS

The surgical stapling instrument of the present disclosure will now be described in detail with reference to the drawings in which like reference numerals designate identical or corresponding elements in each of the several views. In this description, the term “proximal” is used generally to refer to that portion of the device that is closer to a clinician, while the term “distal” is used generally to refer to that portion of the device that is farther from the clinician. In addition, the term clinician is used generally to refer to medical personnel including doctors, nurses, and support personnel.

The surgical stapling instrument of the present disclosure includes an anvil body, a cartridge body, an actuator or lever that is configured to move the anvil body and the staple cartridge between a spaced position and a clamped position, and a firing member. A staple cartridge, such as a single use loading unit (SULU) or multi-use loading unit (“MULU”), is mountable to the cartridge body. The stapling instrument further includes a lockout member which prevents actuation of the firing member until the staple cartridge is properly installed on the cartridge body. The firing member includes structural features which increase the compressive strength of the firing member thereby enabling firing of multiple rows of staples, e.g., two sets of three rows of staples, from the staple cartridge with relative ease and without deformation of any segment of the firing member. The firing member defines a reduced profile, particularly compared to conventional stapling instruments which incorporate a double channel or U-shaped drive to deploy staples.

FIGS. 1-2 illustrate an exemplary embodiment of a surgical stapling instrument incorporating the lockout member and the firing member of the present disclosure, and designated generally as stapling instrument 10. The stapling instrument 10 includes an anvil body 12 defining a longitudinal axis “k”, a cartridge body 14 supporting a clamping lever 16, a staple cartridge or single use loading unit (“SULU”) 18 mountable to the cartridge body 14 and a firing assembly 20. The cartridge body 14 includes a cartridge support column 22 having a proximal segment 24 and a distal segment 26. The proximal segment 24 of the cartridge support column 22 receives the firing assembly 20 and pivotally supports the clamping lever 16. The distal segment 26 of the cartridge support column 22 receives the staple cartridge 18. The anvil body 12 includes an anvil hand grip 28 and an anvil plate 30. The clamping lever 16 is pivotally supported on the cartridge body 14 and is engageable with the anvil body 12 such that movement of the clamping lever 16 from an unclamped position (FIG. 2) to a clamped position (FIG. 1) moves the anvil body 12 into close approximation with the cartridge body 14. The firing assembly 20 includes a firing lever 32 and a firing member 34 extending from the firing lever 32. In general, with the clamping lever 16 in the clamped position with tissue to be joined between the staple cartridge 18 and the anvil plate 30, the firing assembly 20 is actuated by advancing movement along the longitudinal axis “k” whereby the firing member 34 cooperates with staple pushers (not shown) within the staple cartridge 18 to eject a plurality of rows of staples from the staple cartridge 18 for engagement and deformation by the anvil plate 30. In embodiments, the staple cartridge 18 accommodates two sets of three rows of staples that are delivered through tissue. A knife (not shown) may traverse the staple cartridge 18 to sever tissue between the two sets of rows of staples.

For a detailed discussion of the construction and operation of an exemplary surgical stapling instrument, reference may be made to commonly assigned U.S. Pat. No. 8,505,801 to Ehrenfels et al., the entire contents of which are incorporated herein by reference.

Referring now to FIGS. 3-6, the stapling instrument 10 includes a lockout member 36 which is mounted relative to the firing member 34. The lockout member 36 is supported by the cartridge body 14 and is movable between a locked position engaging the firing member 34 and a release position releasing the firing member 34. The lockout member 36 includes a lockout base 38 defining a single longitudinal slot 40 for at least partial reception of the firing member 34. The single longitudinal slot 40 of the lockout member 36 includes a first lower slot portion 40 a and a second upper slot portion 40 b. As best depicted in FIG. 4, the first slot portion 40 a defines a first dimension “d1” orthogonal to the longitudinal axis “k” and the second slot portion 40 b defines a second dimension “d2” orthogonal to the longitudinal axis “k”. The first dimension “d1” is greater than the second dimension “d2”.

The lockout member 36 includes a lockout shelf 42 (FIG. 5) depending from the front or distal end of the lockout base 38. The lockout shelf 42 defines a triangular shape in cross-section and is configured to engage corresponding structure of the firing member 34 to prevent advancement, i.e., distal longitudinal movement, of the firing assembly 20 when the lockout member 36 is in the locked position. The lockout member 36 further includes a stop 44 extending from the lockout shelf 42 in the proximal direction. The stop 44 is configured to engage corresponding structure of the firing member 34 to prevent proximal movement of the firing member 34, e.g., prior to use of the instrument 10. The stop 44 may extend within the longitudinal slot 40 of the lockout base 38.

The lockout member 36 further includes a pair of release legs 46 depending from the rear or proximal end of the lockout base 38. The release legs 46 are engaged by the staple cartridge 18 when the staple cartridge 18 is installed relative to the cartridge body 14 to move the lockout member 36 from the locked position to the release position. The release legs 46 may include arcuate raised segments 48 to enhance engagement with the staple cartridge 18.

The lockout member 36 includes a pair of pivot bosses 50 depending radially outwardly from the lockout base 38. The pivot bosses 50 are received within corresponding openings 52 (one is shown in FIG. 7) in the opposed walls 14 a, 14 b of the cartridge body 14 to pivotally mount the lockout member 36 to the cartridge body 14. The pivot bosses 50 may define chamfered surfaces 54 to facilitate positioning within the openings 52 of the cartridge body 14. The lockout member 36 is capable of pivotal movement between the locked position and the release position via the pivot bosses 50. As best depicted in FIG. 6, a torsion spring 56 is mounted about one of the pivot bosses 50 and is at least partially disposed within a recess 58 in the sidewall of the lockout base 38. The torsion spring 56 engages, at one end, the rear surface of the recess 58 of the lockout base 38 (FIG. 6) and, at its other end, the cartridge body 14. The torsion spring 56 normally biases the lockout member 36 toward its locked position depicted in FIGS. 7-8.

With reference to FIGS. 3 and 6, the firing member 34 will be discussed. The firing member 34 defines a plate-like profile having a lower arcuate segment 60 and a single plate segment 62 extending from the arcuate segment 60. In embodiments, the firing member 34 is manufactured from a single plate of steel or the like which is rolled along one longitudinal end to define the double layered arcuate segment 60. The arcuate segment 60 substantially increases the compressive strength of the firing member 34, which may be required to achieve the forces needed to deliver staples of a staple cartridge 18 having multiple rows of staples, e.g., two sets of three rows of staples. The arcuate segment 60 resides within the first slot portion 40 a of the longitudinal slot 40 of the lockout base 38 and the plate segment 62 resides in the second slot portion 40 b of the longitudinal slot 40. The firing member 34 traverses the longitudinal slot 40 of the lockout base 38 during activation of the firing assembly 20.

Referring now to FIGS. 7-10, further details of the lockout member 36 and the firing member 34 will be discussed. In FIGS. 7-10, the lockout member 36 is in the locked position securing the firing member 34 in an initial proximal position thereof via the biasing effect of the torsion spring 56. The staple cartridge 18 is not installed or mounted with respect to the cartridge body 14. In the locked position, the lockout shelf 42 of the lockout member 36 is disposed within a correspondingly dimensioned lockout recess 64 (FIGS. 9 and 10) of the firing member 34. The lockout recess 64 may be polygonal in shape although other configurations are also envisioned. In embodiments, the lockout recess 64 is defined in part by a distal oblique surface 66 (FIG. 10) with which the lockout shelf 42 engages to retain the lockout member 36 in the locked position and the firing member 34 in the initial proximal position. The lockout recess 64 is also defined in part by a proximal stop surface 68 which is engaged by the stop 44 of the lockout member 36 in the event the firing member 34 is pulled in a proximal direction, e.g., prior to use of the stapling instrument, to prevent displacement of the firing member 34.

FIGS. 11-13 illustrate the staple cartridge 18 mounted to the cartridge body 14, and its corresponding effect on the lockout member 36. Upon mounting of the staple cartridge 18 to the distal segment 26 of the cartridge body 14, the release legs 46 including the arcuate raised segments 48 are engaged by the staple cartridge 18 and move in a downward direction toward the cartridge body 14 (FIG. 12). This causes the lockout member 36 to pivot about the pivot bosses 50 in a counterclockwise direction (relative to FIGS. 12-13) against the bias of the torsion spring 56 and within the cartridge body 14, thereby lifting and releasing the lockout shelf 42 from the lockout recess 64 of the firing member 34. With the lockout shelf 42 in the release position, the firing member 34 may be longitudinally advanced toward the actuated distal position as depicted in FIG. 14 to drive the staples (not shown) from the staple cartridge 18.

Thus, the lockout member 36 and associated firing member 34 cooperate to ensure the staple cartridge 18 is properly installed before the firing member 34 may be activated. The firing member 34 defines a reduced plate-like profile configured to traverse the single longitudinal slot 40 of the lockout member 36, and is capable of delivering forces sufficient to deploy multiple rows of staples. The reduced profile of the firing member potentially creates additional space for the other operating components of the stapling instrument.

Although the presently disclosed surgical stapling instrument 10 is illustrated as an open-type linear surgical stapler, it is envisioned that the benefits of the present disclosure may be incorporated into a variety of different types of surgical stapling instruments including, e.g., endoscopic linear staplers.

Persons skilled in the art will understand that the devices and methods specifically described herein and illustrated in the accompanying drawings are non-limiting exemplary embodiments. It is envisioned that the elements and features illustrated or described in connection with one exemplary embodiment may be combined with the elements and features of another without departing from the scope of the present disclosure. As well, one skilled in the art will appreciate further features and advantages of the disclosure based on the above-described embodiments. Accordingly, the disclosure is not to be limited by what has been particularly shown and described, except as indicated by the appended claims. 

What is claimed is:
 1. A surgical stapling instrument, comprising: an anvil body defining a longitudinal axis; a cartridge body coupled to the anvil body; a staple cartridge releasably mounted relative to the cartridge body; a firing member mounted to the cartridge body and configured for longitudinal movement through the staple cartridge; and a lockout member supported by the cartridge body, the lockout member defining a single longitudinal slot for at least partial reception of the firing member, the lockout member configured for movement from a locked position preventing longitudinal movement of the firing member to a release position permitting longitudinal movement of the firing member upon mounting of the staple cartridge to the cartridge body.
 2. The surgical stapling instrument according to claim 1 wherein the lockout member includes a lockout shelf and the firing member includes a lockout recess, the lockout shelf configured to engage the lockout recess when in the locked position of the lockout member, and configured to release the lockout recess when in the release position of the lockout member.
 3. The surgical stapling instrument according to claim 2 wherein the lockout member is pivotally mounted to the cartridge body, the lockout member being configured for pivotal movement between the locked position and the release position.
 4. The surgical stapling instrument according to claim 3 wherein the lockout member is normally biased toward the locked position.
 5. The surgical stapling instrument according to claim 4 including a spring coupled to the lockout member and operatively engageable with the cartridge body, the spring configured to normally bias the lockout member toward the locked position.
 6. The surgical stapling instrument according to claim 5 wherein the spring is a torsion spring.
 7. The surgical stapling instrument according to claim 4 wherein the lockout member includes at least one release leg configured to be engaged by the staple cartridge upon mounting of the staple cartridge to the cartridge body to facilitate movement of the lockout member from the locked position to the release position.
 8. The surgical stapling instrument according to claim 7 wherein the at least one release leg includes an arcuate raised segment.
 9. The surgical stapling instrument according to claim 2 wherein the firing member is configured for longitudinal movement between an initial proximal position and an actuated distal position.
 10. The surgical stapling instrument according to claim 9 wherein the lockout member includes a stop proximal of the lockout shelf, the stop configured to engage the lockout recess of the firing member to prevent proximal movement of the firing member beyond the initial proximal position.
 11. The surgical stapling instrument according to claim 9 wherein the firing member is configured to traverse the single longitudinal slot of the lockout member during movement of the firing member between the initial proximal position and the actuated distal position.
 12. The surgical stapling instrument according to claim 11 wherein the firing member includes a lower arcuate segment and a plate segment.
 13. The surgical stapling instrument according to claim 12 wherein the single longitudinal slot of the lockout member includes a first slot portion configured for accommodating the arcuate segment of the lockout member and a second slot portion configured for accommodating the plate segment of the firing member.
 14. The surgical stapling instrument according to claim 13 wherein the first slot portion defines a first dimension orthogonal to the longitudinal axis and the second slot portion defines a second dimension orthogonal to the longitudinal axis, the first dimension being greater than the second dimension. 